From patchwork Fri Oct 22 15:36:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Bonzini X-Patchwork-Id: 12578051 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 287D6C433EF for ; Fri, 22 Oct 2021 15:36:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13FBC611BD for ; Fri, 22 Oct 2021 15:36:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233538AbhJVPiv (ORCPT ); Fri, 22 Oct 2021 11:38:51 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:31837 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233403AbhJVPis (ORCPT ); Fri, 22 Oct 2021 11:38:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1634916990; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qEjgWJbpNIJZQvyAdA2aZae0irmK7CDWwgTx4nE6Fnc=; b=i6wE7pbVzRXKMfYmV7KI3Z56p03F10ozNh+ZIA3MdIdZ8fgArHkVHzuobXAVxjZfxOhKJt bLSXI5R4aoBBe+a9X6uJ2jUBU2L4SSqvyFl4virnhEgQ9JggEfip+meBPe2ocXYVTehH24 G2o5OGAeG0mRICQdAdbjL6T/VTxvVOM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-141-GxHlLUyqMmKzl0yEBHmAqw-1; Fri, 22 Oct 2021 11:36:27 -0400 X-MC-Unique: GxHlLUyqMmKzl0yEBHmAqw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7E9E3362FE; Fri, 22 Oct 2021 15:36:26 +0000 (UTC) Received: from virtlab701.virt.lab.eng.bos.redhat.com (virtlab701.virt.lab.eng.bos.redhat.com [10.19.152.228]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1FE6C60C04; Fri, 22 Oct 2021 15:36:26 +0000 (UTC) From: Paolo Bonzini To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: mlevitsk@redhat.com, seanjc@google.com Subject: [PATCH 08/13] KVM: x86: inline kernel_pio into its sole caller Date: Fri, 22 Oct 2021 11:36:11 -0400 Message-Id: <20211022153616.1722429-9-pbonzini@redhat.com> In-Reply-To: <20211022153616.1722429-1-pbonzini@redhat.com> References: <20211022153616.1722429-1-pbonzini@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The caller of kernel_pio already has arguments for most of what kernel_pio fishes out of vcpu->arch.pio. This is the first step towards ensuring that vcpu->arch.pio.* is only used when exiting to userspace. We can now also WARN if emulated PIO performs successful in-kernel iterations before having to fall back to userspace. The code is not ready for that, and it should never happen. No functional change intended. Signed-off-by: Paolo Bonzini Reviewed-by: Maxim Levitsky --- arch/x86/kvm/x86.c | 39 +++++++++++++++++---------------------- 1 file changed, 17 insertions(+), 22 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b26647a5ea22..d6b8df7cea80 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6886,37 +6886,32 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, return emulator_write_emulated(ctxt, addr, new, bytes, exception); } -static int kernel_pio(struct kvm_vcpu *vcpu, void *pd) -{ - int r = 0, i; - - for (i = 0; i < vcpu->arch.pio.count; i++) { - if (vcpu->arch.pio.in) - r = kvm_io_bus_read(vcpu, KVM_PIO_BUS, vcpu->arch.pio.port, - vcpu->arch.pio.size, pd); - else - r = kvm_io_bus_write(vcpu, KVM_PIO_BUS, - vcpu->arch.pio.port, vcpu->arch.pio.size, - pd); - if (r) - break; - pd += vcpu->arch.pio.size; - } - return r; -} - static int emulator_pio_in_out(struct kvm_vcpu *vcpu, int size, unsigned short port, unsigned int count, bool in) { + void *data = vcpu->arch.pio_data; + unsigned i; + int r; + vcpu->arch.pio.port = port; vcpu->arch.pio.in = in; - vcpu->arch.pio.count = count; + vcpu->arch.pio.count = count; vcpu->arch.pio.size = size; - if (!kernel_pio(vcpu, vcpu->arch.pio_data)) - return 1; + for (i = 0; i < count; i++) { + if (in) + r = kvm_io_bus_read(vcpu, KVM_PIO_BUS, port, size, data); + else + r = kvm_io_bus_write(vcpu, KVM_PIO_BUS, port, size, data); + if (r) + goto userspace_io; + data += size; + } + return 1; +userspace_io: + WARN_ON(i != 0); vcpu->run->exit_reason = KVM_EXIT_IO; vcpu->run->io.direction = in ? KVM_EXIT_IO_IN : KVM_EXIT_IO_OUT; vcpu->run->io.size = size;